Coalescence of Pore Columns by Domain Switching

The present paper studies the coalescence of pore columns in ferroelectric ceramics driven by back and forth domain switching under cyclic electric field. A finite element method that incorporates mass transfer capacity is formulated to simulate the evolution of point defects subjected to the kinetics of pore surface diffusion and domain wall migration. The merge of point defects provides a mechanism for the vacancy agglomeration that leads to the formation of large pores or microcracks.The project supported by the National Natural Science Foundation of China (10332020 and 10121202), and the National 973 Project (2004CB619304).